Ultra high frequency tube



Nov. 30; 1 948. I H. J, MCCARTHY 2,455,310

ULTRA HIGH FREQUENCY TUBE Filed Dec. 10, 1945 INVENTOR.

F770;? HE Y Patented Nov. 30, 1948 ULTRA HIGH FREQUENCY TUBE Henry J. McCarthy, Danvers, Mass, assignor to Sylvania Electric Products Inc., Salem, Mass,

a corporation of Massachusetts Application December 10, 1945, Serial No. 633,967

4 Claims. (01. 250-275) This application relates to ultra-high frequency radio tubes and the like, and particularly to such tubes including resonators as part thereof, such as the vane type magnetron.

An object of the invention is to increase the power output of such a tube. is to simplify the construction of the tube, and still another object is to permit direct coupling of small vane-type magnetrons to a coaxial cable.

A further object by the passage of current in filament 2|. End plate 23 closes oil the bottom end of compartment 1. My coupling means 24 extends from lead-in I? into the compartment spaced somewhat from the vanes H9 in annular compartment I.

The shape of this coupling element 24 is clear from Figure 4, which shows it extending along and spaced above a vane 19 across the space between two such vanes and along the second vane A feature of the invention is. an ultra-high fre- 10 I9 toward the base of said vane. The end 26 quency tube of increased output. of said coupling wire remains free and is not in A further feature of the invention is an 11 1- contact with the metal piece 28 or the vanes l9. grounded or open-circuited coupling loop, in In operation, a magnetic field is directed transproximity to a vane resonator chamber. versely through the device, from end plate 2 to Other objects, features and advantages of the 5 end plate 23, current passed through filament 2| invention will be apparent from the following to heat cathode cylinder 22, and a source of voltspecification taken with the accompanying drawage placed between said cathode and the vanes ings in which: l9 and compartment l which is made positive.

Figure 1 is an external perspective view of a The device will generally be provided with such sealed device according to the invention; tage in s t p s, s t the tp also Figure 2 is a view of the same device, with its will be in short pulses. During each pulse, the top plate and cathode removed to show interior eiTect of the electrostatic and magnetic fields on details; the motions of electrons between cathode 22 and Figure 3 is a cross section of the device; and vanes !9 will be such as to produce oscillations of Figure 4 is an interior view of the device partly 25 an ultra-high freque y fixed by t e d e 0ns in section. of the device. The wire 24 will couple these oscil- In Figure l the metal compartment l is herlations to the external circuit in which they are metically sealed by plate 2, which may be affixed t9 be usedthereto by soldering or welding, for example by In previous devices, the hook-like member 24 indium-gold solder or other well-known means. was made in the form of a nearly closed loop Plate s with flange a is attached to the comparthi w s t a y s d y having its f ment i to facilitate mounting of the device and end fixed to the internal annular g portion 28 connections to the remainder of the circuit. of the devicen y a small D could e o Metal pipes or coaxial cables 5 and 6 extend out tained th this e e t, and t s abanof the compartment I terminating in glass tubes Cloned in fever o a p ic d Wa u de a1"- T, 8, sealed at their outer ends 9, l0 through which rangement wh ec s d a slot being Cut lead-in wires H and i2 project, with lead-in wire through th annular ring 3 d p ed to a I3 emerging at the side M of tube 8. From the l e W e d other end a pipe l5 extends, terminating in a In my device the piece 24 is not connected at coaxial cable IS with a short small glass tube I6 4 its end 26 to piece 28, and no wave-guide is used, attached thereto, with the central Wire I1 of the y I Obtain more than three times the D cable extending therefrom. merly obtainable without the wave guide, and

In Figure 2, the top plate 2 is removed, so that more power than can be obtained with the wave the annular piece 28 with its vanes I9 is shown, guide itself. In addition, my device is simple to together with the inside end of filament lead-in make, and does not necessitate the complicated wire l2, which is shown entering through a hole machinery of a wave guide. in piece 20 which attaches the pipes 5 to the My coupling wire 26 is spaced from vanes l9, Walls partment i. and must thus be electrostatically coupled there- The metal filament or heater wire 2! to which to; and yet it is shaped to the form of a split magthe lead-in i2 is connected is shown in Figure 3. netically coupled loop.

It is surrounded by the metal cylinder 22, closed t I claim i at its ends, through which the lead-ins to the l. A vane type magnetron, a single coupling filament extend through an s t g b n loop comprising a wire extending partway along The metal cylinder is coated with alkaline earth one vane, but spaced therefrom crossing the space oxides to become electron-emissive when heated between vanes, and extendin along an adjacent vane in the opposite direction and spaced therefrom to form an approximately U-shaped openended loop.

2. A vane type magnetron, a coaxial cable extending thereinto and terminating in an openended ungrounded U-shaped coupling loop in which each of the legs of the U is approximately parallel to but spaced from one of at least two adjacent vanes.

3. A magnetron comprising: an annular metal member with spaced metal vanes projecting in.- ward from its inside circumference; a coaxial cable outside of the annular member and extending theretoward, said cable having an, outer metal cylinder conductively connected tosaid annular member and aligned with one of said vanes, and an inner wire coaxial with said outer cylinder and extending longitudinally outward from an end of said outer cylinder and partway 15 Number along the aligned vane, then across the space between vanes and along an adjacent vane in the opposite direction to form a loop spaced from said vanes and from said annular member.

4. The combination of claim 3, in which the wire extends along said vanes for approximately half the length of the latter.

HENRY J. MCCARTHY.

REFERENCES CITED The following references are of record in the file. at this patent:

UNITED STATES PATENTS Name Date Fritz et al Apr. 26, 1938 Spencer Sept. 24, 1946 Hansell' Oct. 8, 1946 Laico et a1 Apr. 29, 1947 

